Flexible commissure frame

ABSTRACT

Prosthetic devices and frames for implantation at a cardiac valve annulus are provided that include an annular frame (having an inflow end and an outflow end) and a plurality of axial frame members that bridge two circumferentially extending rows of angled struts. The axial frame members can include a plurality of axially extending leaflet attachment members and a plurality of axial struts in a 1:1 ratio. Along each of the two rows, the frame can have at least three angled struts between adjacent axial frame members.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. ProvisionalApplication No. 61/941,123, filed Feb. 18, 2014, which is incorporatedherein by reference.

FIELD

This disclosure is in the field of prosthetic heart valves, stents foruse with prosthetic heart valves, and methods for delivering prostheticheart valves.

BACKGROUND

Existing frames for prosthetic heart valves typically comprise rows ofangled struts and a plurality of axial frame members spaced apart aroundthe circumference of the frame. The plurality of axial frame members maycomprise a plurality of leaflet attachment members (for attaching to thecommissures of the supported valvular structure) and a multitude ofaxially directed struts extending between the rows of angled struts. Aframe usually has three or more axially directed struts for everyleaflet attachment member, and generally has no more than two angledstruts located in between adjacent struts or other axial frame members.Indeed, having a large number of axially directed struts is perceived tobe necessary for preserving the structural stability of the stent and/orvalve. Unfortunately, having a large number of axial struts can come atthe expense of valve flexibility.

A need therefore exists for stents and prosthetic valves that can have ahigh degree of flexibility, without compromising mechanical integrity orfunction.

SUMMARY

In one aspect of the disclosure, a prosthetic device for implantation ata cardiac valve annulus has an annular frame with an inflow end, anoutflow end, and a plurality of axial frame members bridging twocircumferentially extending rows of angled struts, wherein the pluralityof axial frame members comprises a plurality of axially extendingleaflet attachment members and a plurality of axial struts in a 1:1ratio.

In some embodiments, the device can further comprise a leaflet structurepositioned within the frame, the leaflet structure having a plurality ofcommissures that are secured to the frame at the leaflet attachmentmembers.

In some embodiments, at least three angled struts separate adjacentaxial frame members along each of the two rows of angled struts.

In some embodiments, exactly six angled struts separate adjacent leafletattachment members along each of the two rows of angled struts, andexactly three angled struts separate adjacent axial frame members alongeach of the two rows of angled struts, such that each axial strut ispositioned halfway between adjacent leaflet attachment members.

In some embodiments, each axial frame member extends between locationsdefined by the convergence of adjacent angled struts.

In some embodiments, the device further comprises an inner skirt securedto an interior portion of the annular frame, and an outer skirt securedto an exterior portion of the annular frame.

In some embodiments, the frame comprises exactly four rows of angledstruts.

In some embodiments, the valve member comprises exactly three leafletsarranged in a tricuspid configuration, wherein the frame comprisesexactly three axial struts and exactly three leaflet attachment members,and wherein the exactly three angled struts separate adjacent axialframe members along each of the two rows of angled struts.

In another aspect of the disclosure, an annular frame for a prostheticheart valve can comprise an inflow end, an outflow end, and a pluralityof axial frame members spaced angularly around the circumference of theframe. The plurality of axial frame members can bridge twocircumferentially extending rows of angled struts, wherein each of thetwo rows comprise at least three angled struts between adjacent axialframe members.

In some embodiments, each of the two rows comprises exactly three angledstruts between adjacent axial frame members.

In some embodiments, the plurality of axial frame members comprises aplurality of axially extending leaflet attachment members, and each ofthe two rows comprises exactly six angled struts between adjacentleaflet attachment members.

In some embodiments, the plurality of axial frame members comprises aplurality of axially extending leaflet attachment members, wherein eachof the two rows comprises four angled struts between adjacent axialframe members and eight angled struts between adjacent leafletattachment members.

In some embodiments, the plurality of axial frame members comprisesexactly three leaflet attachment members and exactly three axial struts.

In some embodiments, the leaflet attachment members extend betweenlocations defined by the convergence of the upper ends of adjacentangled struts of each row of angled struts, and the axial struts extendbetween locations defined by the convergence of the lower ends ofadjacent angled struts of each row of angled struts.

In some embodiments, the two rows of angled struts can comprise a firstrow and a second row, wherein the first row is closer to the outflow endthan the second row.

In some embodiments, the leaflet attachment members extend fromlocations defined by the convergence of the upper ends of adjacentangled struts along the first row of angled struts to locations definedby the convergence of the lower ends of adjacent angled struts along thesecond row of angled struts, and the axial struts extend betweenlocations defined by the convergence of the lower ends of adjacentangled struts along the first row of angled struts to locations definedby the convergence of upper ends of adjacent angled struts along thesecond row of angled struts.

In some embodiments, the leaflet attachment members extend fromlocations defined by the convergence of the upper ends of adjacentangled struts along the first row of angled struts to locations definedby the convergence of the upper ends of adjacent angled struts along thesecond row of angled struts, and the axial struts extend betweenlocations defined by the convergence of the lower ends of adjacentangled struts along the first row of angled struts to locations definedby the convergence of lower ends of adjacent angled struts along thesecond row of angled struts.

In some embodiments, the frame comprises exactly four rows of angledstruts.

In another aspect of the disclosure, a prosthetic device forimplantation at a cardiac valve annulus is provided, comprising anannular frame having an inflow end, an outflow end, at least four rowsof circumferentially extending angled struts, and exactly six axialframe members bridging two rows of the four rows of circumferentiallyextending angled struts. The plurality of axial frame members cancomprise exactly three axially extending leaflet attachment members andexactly three axial struts, wherein each of the two rows comprisesexactly three angled struts between each adjacent pair of a leafletattachment member and an axial strut, and exactly six angled strutsbetween adjacent leaflet attachment members. The device can furthercomprise a tri-leaflet valve member positioned within the frame havingcommissures that are secured to the frame at the leaflet attachmentmembers.

The foregoing and other objects, features, and advantages of theinvention will become more apparent from the following detaileddescription, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 show side and perspective views of an exemplary embodimentof a prosthetic heart valve.

FIGS. 3-5 show side, perspective, and flattened views of an exemplaryframe of the prosthetic heart valve of FIG. 1.

FIG. 6 is a perspective view of another exemplary prosthetic heartvalve.

FIGS. 7-8 show perspective and flattened views of an exemplary frame ofthe prosthetic heart valve of FIG. 6.

FIG. 9 shows a flattened view of another exemplary frame for aprosthetic heart valve.

FIG. 10 shows a flattened view of a portion of another exemplary framefor a prosthetic heart valve.

FIG. 11 shows a flattened view of a portion of another exemplary framefor a prosthetic heart valve.

FIG. 12 shows a flattened view of a portion of another exemplary framefor a prosthetic heart valve.

FIG. 13 shows a flattened view of a portion of another exemplary framefor a prosthetic heart valve.

DETAILED DESCRIPTION

Disclosed herein are prosthetic heart valves and stents for use withsuch valves that are capable of a high degree of flexibility. Thisflexibility can be useful for delivery to the valve annulus (such as forcrimping/expanding a transcatheter heart valve (THV)) and/or foraccommodating movement of the valve during cardiac cycling. Inparticular embodiments, strategically selected locations around thecircumference of the frame are without axial struts, resulting in theimproved flexibility. In various embodiments, the flexibility of thecommissures is enhanced as a result of an increase in the distancebetween each commissure and the nearest axial frame member (other thanany support member located at the commissure such as a commissuresupport or window frame member). The frame can have one or morecircumferentially extending rows of struts with three continuous angledstruts between one or more pairs of axial supports. In some embodiments,these one or more rows of struts are located towards an outflow end ofthe frame. In some embodiments, the frame can have two rows ofcircumferentially extending struts (towards the outflow end of thevalve) having three continuous angled struts between pairs of axialsupports. In some embodiments, the frame has three continuous angledstruts separating each commissure support (located at each commissure)from the nearest axial support. In another embodiment, there are foursuch angled struts separating each commissure support from the nearestaxial strut.

As used herein, an “axial support” is a junction where at least threestruts are connected, such as two angled struts connecting to a singleaxial strut or a junction of two angled struts and another axial membersuch as a commissure support. As used herein, an “axial frame member” isany axially extending support member that connects two (or more)circumferentially extending rows of angled struts. Thus, an axial framemember can be an axial support member that engages one or more leaflets,such as a commissure support. An axial frame member can also be a simpleaxial strut or other axial member that does not engage a leaflet. Asused herein, a “commissure support” (also referred to as a “leafletattachment member”) is an axially extending support member configured tosupport a respective commissure of a prosthetic valve member. Acommissure support can be a commissure “window frame member” configuredto receive a commissure of a prosthetic valve member through an openingin the frame member, as further described below. A commissure supportcan also be an axial strut or other axial support member that does notinclude a window or other opening sized to receive a commissure. Assuch, a commissure can be supported by a leaflet attachment member usingvarious techniques or mechanisms, such as by securing commissures torespective leaflet attachment members with sutures extending throughsuture openings in the leaflet attachment members.

FIGS. 1-2 show a prosthetic heart valve 100, according to one embodimentin side view and in perspective, respectively. The illustratedprosthetic valve is adapted to be implanted in the native aorticannulus, although in other embodiments it can be adapted to be implantedin the other native annuluses of the heart (i.e., the native mitral,pulmonary, and tricuspid valves) or in other tubular passageways in thebody. The valve 100 can have four main components: a stent or frame 102,a valvular structure 104, an inner skirt 106, and an outer skirt 108.The frame 102 can have an inflow end 103 and an outflow end 105.

The valvular structure 104 can comprise three leaflets 110, collectivelyforming a leaflet structure, which can be arranged to collapse in atricuspid arrangement. The leaflets 110 can be secured to one another attheir adjacent sides to form commissures. The leaflets 110 can be formedof pericardial tissue (e.g., bovine pericardial tissue), biocompatiblesynthetic materials, or various other suitable natural or syntheticmaterials as known in the art and described in U.S. Pat. No. 6,730,118,which is incorporated by reference herein.

The bare frame 102 is shown in FIGS. 3-5 in a side view, a perspectiveview, and an unrolled and flattened configuration, respectively. Theframe 102 can be formed with a plurality of circumferentially spacedslots, or commissure windows 120 (three in the illustrated embodiment),that are adapted to mount the commissures of the valvular structure 104to the frame, as described in greater detail below. The frame 102 can bemade of any of various suitable plastically-expandable materials (e.g.,stainless steel, etc.) or self-expanding materials (e.g., nitinol) asknown in the art.

Suitable plastically-expandable materials that can be used to form theframe 102 can include, without limitation, stainless steel, a nickelbased alloy (e.g., a cobalt-chromium or a nickel-cobalt-chromium alloy),polymers, or combinations thereof. In particular embodiments, the frame102 can be made of a nickel-cobalt-chromium-molybdenum alloy, such asMP35N® alloy (SPS Technologies), which is equivalent to UNS R30035 alloy(covered by ASTM F562-02). MP35N®/UNS R30035 alloy comprises 35% nickel,35% cobalt, 20% chromium, and 10% molybdenum, by weight. It has beenfound that the use of MP35N® alloy to form the frame 102 can providesuperior structural results over stainless steel. In particular, whenMP35N® alloy is used as the frame material, less material is needed toachieve the same or better performance in radial and crush forceresistance, fatigue resistances, and corrosion resistance. Moreover,since less material is required, the crimped profile of the frame 102can be reduced, thereby providing a lower profile valve assembly forpercutaneous delivery to the treatment location in the body.

When constructed of a plastically-expandable material, the frame 102(and thus the valve 10) can be crimped to a radially compressed state ona delivery catheter and then expanded inside a patient by an inflatableballoon or equivalent expansion mechanism. When constructed of aself-expandable material, the frame 102 (and thus the valve 100) can becrimped to a radially compressed state and restrained in the compressedstate by insertion into a sheath or equivalent mechanism of a deliverycatheter. Once inside the body, the valve can be advanced from thedelivery sheath, which allows the valve to expand to its functionalsize.

Referring to FIG. 5, the frame 102 (shown in a flattened configuration)in the illustrated embodiment comprises a first, lower row I of angledstruts 112 arranged end-to-end and extending circumferentially at theinflow end of the frame; a second row II of circumferentially extending,angled struts 114; a third row III of circumferentially extending,angled struts 116; a fourth row IV of circumferentially extending,angled struts 118; and a fifth row V of circumferentially extending,angled struts 122 at the outflow end 105. A plurality of substantiallystraight, axially extending struts 124 can be used to interconnect thestruts 112 of the first row I with the struts 114 of the second row II.The fifth row V of angled struts 122 are connected to the fourth row IVof angled struts 118 by a plurality of axially extending window frameportions 130 (which define the commissure windows 120) and a pluralityof axially extending struts 132.

Each commissure window frame portion 130 mounts a respective commissureof the valvular structure 104. As can be seen, each window frame portion130 is secured at its upper and lower ends to the adjacent rows ofangled struts to provide a robust configuration that enhances fatigueresistance under cyclic loading of the valve compared with known framesusing cantilevered struts for supporting the commissures of the leafletstructure. This configuration enables a reduction in the frame wallthickness to achieve a smaller crimped diameter of the valve. Inparticular embodiments, the thickness of the frame 12 as measuredbetween the inner diameter and outer diameter is about 0.48 mm or less.

As best shown in FIGS. 3-4, the struts and frame portions of the framecollectively define a plurality of open cells of the frame. At theinflow end of the frame 102, struts 112, struts 114, and struts 124define a lower row of cells defining openings 136.

In some embodiments, there are fewer than three axially extending struts132 between adjacent window frame portions 130, along the length of therows, such as only two axially extending struts 132 or only one axiallyextending strut 132. In some embodiments, there is only one axiallyextending strut 132 in between adjacent window frame portions 130, whichcan be located halfway in between the window frame portions 130. Thus,in various embodiments, the frame can be specifically constructed tointegrate window frame portions 130 and axially extending struts 132 ina 1:1 ratio.

In one embodiment illustrated in FIGS. 3-5, there are exactly threewindow frame portions 130 and exactly three axial struts 132. Minimizingor reducing the number of axially extending struts 132 between windowframe portions 130 promotes more compact crimping of the prostheticvalve. This also maximizes or increases the size of openings 140, which,for example, is advantageous in cases where the outflow end 105 of theprosthetic valve extends higher than the level of the coronary ostia. Insuch cases, the larger openings 140 can provide access to the coronaryarteries for future procedures, such as procedures requiringcatheterization of the coronary arteries.

Each window frame portion 130 and/or each axially extending strut 132can each extend between locations 142 characterized by the convergenceof the lower ends of two angled struts 122 (of row V, at the outflow end105) to locations or nodes 144 defined by the convergence of the upperends of two angled struts 118 (of row IV). There can be two angledstruts 122 along row V from one location 142 to the next location 142,and two angled struts 118 along row IV from one location 144 to the nextlocation 144.

The frame 102 can comprise an axially extending frame member (i.e., aframe portion 130 or a strut 132) at every other such pair of suchlocations 142, 144 along the rows V and VI, respectively. The frame 102can have a window frame portion 130 every four such locations, andspaced equally apart around the circumference of the frame 102, whichcan provide for a total of three window frame portions 130(corresponding to the three commissures in a tri-leaflet valve). Thus,the frame 102 can comprise, in sequence along the row V, a window frameportion 130 extending between a pair of such locations 142, 144 followednext by a second pair of locations 142, 144 lacking an axially extendingstrut or frame member extending therebetween, followed then by anaxially extending strut 132 extending between a third pair of locations142, 144, followed then by a fourth pair of locations 142, 144 againlacking an axially extending strut or frame member, followed by anotherwindow frame portion 130 extending between a pair of such locations 142,144 (and thus re-starting the sequence of struts and frame portions).With two angled struts (along each of rows IV and V) between each set oflocations 142, 144, this embodiment can thus have sets of eight angledstruts between adjacent window frame portions 130, along each row, withfour continuous angled struts between each window frame portion 130 andits adjacent axial struts 132 (i.e., no other axial frame members inbetween).

After the prosthetic heart valve 100 is properly implanted at the valveannulus, the prosthetic valve 100 can cycle between open and closedstates to permit or restrict the flow of blood. In various embodiments,the frame 102 of the prosthetic heart valve 100 provides a measure ofdamping during valve closure by bending inwards during diastole, whichrelieves stress on the leaflets. For example, forces that pull thecommissures of the leaflets 110 radially inwards (such as during valveclosure) can also pull areas of the frame immediately adjacent thecommissures (such as the window frame portions 130) radially inward,while the axial struts 132 can be urged radially outward. In variousembodiments, this damping effect (including pulling of the frameportions 130 radially inward and pushing of the axial struts 132radially outward) is enhanced by reducing the number of axial strutspresent along the top rungs (between rows IV and V in valve 100) asdisclosed herein, relative to frames having a greater number of axialframe members (e.g., greater number of axial struts).

The main functions of the inner skirt 106 are to assist in securing thevalvular structure 104 to the frame 102 and to assist in forming a goodseal between the valve 100 and the native annulus by blocking the flowof blood through the open cells of the frame 102 below the lower edge ofthe leaflets 110. The inner skirt 106 desirably comprises a tough, tearresistant material such as polyethylene terephthalate (PET), althoughvarious other synthetic or natural materials can be used. The innerskirt 106 can be secured to the inside of the frame 102 via sutures. Thevalvular structure 104 can be attached to the inner skirt 106 with theassistance of one or more thin PET reinforcing strips (whichcollectively can form a sleeve, not pictured), which can enable securesuturing and protect the pericardial tissue of the leaflet structurefrom tearing. The valvular structure 104 can be sandwiched between theinner skirt 106 and the thin PET strips.

The upper edge portion of the inner skirt 106 can be formed with aplurality of projections that define an undulating shape that generallyfollows the shape of the fourth row of struts 118 (row IV) immediatelyadjacent the lower ends of axial struts 132. In this manner, as bestshown in FIG. 1, the upper edge of inner skirt 106 can be tightlysecured to struts 118 with suture 146. The inner skirt 106 can also besecured to the first, second, and/or third rows of struts 112, 114, and116 (rows I-III), respectively, with suture 146.

The inner skirt 106 can be sutured to the frame 102 at locations awayfrom the suture line attaching the lower edges of the leaflets 110 tothe inner skirt 106, which both reduces concentration of stress at theleaflet-suture-line and increases pliability to the skirt in that area.

As shown in FIGS. 1-2, a plurality of flexible connectors 125 can beused to interconnect each pair of adjacent edges of the leaflets 110 andto mount the leaflets 110 to the commissure window frame portions 130.The flexible connectors 125 can be made from a piece of woven PETfabric, although other synthetic and/or natural materials can be used.Each commissure can comprise two tab portions of two adjacent leaflets.Each commissure can be secured to the frame, for example, by insertingthe tab portions through the commissure windows 120 of the window frameportions 130, and suturing the tab portions to a connector 125 outsideof the frame 102.

The outer skirt 108 can be laser cut or otherwise formed from a strong,durable piece of material, such as woven PET, although other syntheticor natural materials can be used. The outer skirt 108 can have asubstantially straight lower edge and an upper edge defining a pluralityof alternating projections 150 and notches 152. The lower edge of theouter skirt 108 can be sutured to the lower edge of the inner skirt 106at the inflow end of the valve 100. In other embodiments, the innerskirt 106 and outer skirt 108 are integrally manufactured as a singlecomponent. As shown in FIGS. 1-2, each projection 150 can be affixed tothe second rung II of struts 114 of the frame 102 with sutures 154.

Additional details relevant to the securing of the valve member 104,inner skirt 106 and outer skirt 108 to the frame 102 are provided inU.S. Patent Publication 2011/0123529, which is incorporated by referencein its entirety.

In various embodiments, a frame can be constructed to have greater orfewer rows of angled struts than in frame 102, such as four or six rowsof angled struts. In various other frame embodiments, each window frameportion and/or each axially extending strut can extend between twolocations each defined by the convergence of the upper ends of angledstruts. In various embodiments, each window frame portion and/or eachaxially extending strut can extend between two locations each defined bythe convergence of the lower ends of angled struts.

FIG. 6 shows a perspective view of another exemplary prosthetic valve200 with an inner skirt 206, an outer skirt 208, and a valve member 204mounted within a stent 202. The valve member 204 can have a set of threeleaflets 210. A plurality of flexible connectors 225 can be used tointerconnect pairs of adjacent edges of the leaflets 210 and to mountthe leaflets 210 to the commissure window frame portions 230.

FIGS. 7-8 show perspective and flattened, unrolled views of the barestent 202 having an inflow end 203, an outflow end 205, and four rows(I-IV) of struts 214, 216, 218, 222 (instead of five rows as shown inFIGS. 1-5). The fourth row IV of angled struts 222 can be connected tothe third row IV of angled struts 218 by a plurality of axiallyextending window frame portions 230 (which define commissure windows220) and a plurality of axially extending struts 232.

Thus, each window frame portion 230 and each axially extending strut 232can extend between the two rows of angled struts that are closest to theoutflow end 205. In particular, each window frame portion 230 can extendbetween a location 242 defined by the convergence of the upper ends oftwo angled struts 222 and a location 244 defined by the convergence ofthe upper ends of two angled struts 218. Each axially extending strut232 can extend between another location 246 defined by the convergenceof the lower ends of two angled struts 222 and another location 248defined by the convergence of the lower ends of two angled struts 218.

The frame 202 can comprise three window frame portions 230 spacedequally apart around the circumference of the frame 202. As shown, theframe 202 can be constructed to have six angled struts (along each ofrows III and IV) between the window frame portions 230 along each row.The frame can be constructed to have three angled struts between eachwindow frame portion 230 and the adjacent axial struts 232. Thus, eachaxial strut 232 can be located halfway between adjacent window frameportions 230, and the frame 200 can be constructed to integrate windowframe portions and axially extending struts in a 1:1 ratio. In theillustrated embodiment, there are exactly three window frame portions230 and exactly three axial struts 232.

In particular, the frame 202 can comprise, in sequence along the rowsIII and IV, a window frame portion 230 extending between a pair oflocations 242, 244, followed by a pair of locations 246, 248 lacking anaxially extending member, followed by a pair of locations 242, 244lacking an axially extending member, followed by an axially extendingstrut 232 extending between a pair of locations 246, 248, followed by apair of locations 242, 244 lacking an axially extending member, followedby a pair of locations 246, 248 lacking an axially extending member,followed by another window frame portion 230 extending between a pair oflocations 242, 244 (and thus re-starting the sequence of window frameportions 230 and axially extending struts 232).

Once the prosthetic heart valve 200 is properly installed at the valveannulus, the valve 200 can cycle between open and closed states topermit or restrict the flow of blood. As discussed with respect toprosthetic valve 100, forces that pull the commissures radially inwardsduring cycling can also pull the window frame portions 230 radiallyinward to relieve stress on the leaflets during valve closure.Meanwhile, the axial struts 232 can be urged radially outward.

The frame 200 can be capable of assuming a collapsed configuration (suchas for delivery on or within a catheter) and an expanded configuration(i.e., functional configuration at the valve annulus). In variousembodiments, in the collapsed configuration, the plurality of axialstruts is positioned radially outwards relative to the leafletattachment members and/or commissures. In one embodiment, in the processof transitioning from an expanded configuration to a collapsedconfiguration and/or from an collapsed configuration to an expandedconfiguration, the valve 200 can assume an intermediate configuration inwhich only those struts 222 of row IV that are adjacent to an axiallyextending strut 232 are brought together to extend axially (side-by-sideand in substantial axial alignment with struts 232).

In another embodiment, as shown in FIG. 9, a frame 302 can have axialwindow frame members 330 extending between locations 342 defined by theconvergence of the upper ends of two angled struts 322 and locations 344defined by the convergence of the lower ends of two angled struts 318.The frame 302 can have axially extending struts 332 extending betweenlocations 346 defined by the convergence of the lower ends of two angledstruts 322 and locations 348 defined by the convergence of the upperends of two angled struts 318.

Frame 302 is similar to frame 202 except that the first three rows ofangled struts (rows I, II, and III) are shifted 20 degrees relative tothe same rows of frame 202. Thus, each window frame member 330 isaxially aligned with a location 344 defined by the convergence of thelower ends of two angled struts 318 of row III. Each window frame member330 can comprise a lower strut portion 334 below the level of thecommissure window 320 (towards the inflow end of the stent 302). Thislower strut portion 334 extends from the lower end of a window framemember 330 to a location 344 defined by the convergence of the lowerends of two angled struts 318. The lower strut portion 334 providesadded length to the window frame member 330 and allows the frame member330 to effectively bridge the larger distance between locations 342, 344in this embodiment. Other features and components of frame 302 can besimilar to as described above for frame 202.

FIG. 10 shows a portion of a frame 402, according to another embodiment.In FIG. 10, only one-third of the circumference of the two upper rows ofangled struts (the rows closest to the outflow end) is shown. The frame402 can have axial window frame members 430 extending between locations442 defined by the convergence of the lower ends of two angled struts422 and locations 444 defined by the convergence of the lower ends oftwo angled struts 418. The frame 402 can have axially extending struts432 extending between locations 446 defined by the convergence of theupper ends of two angled struts 422 and locations 448 defined by theconvergence of the upper ends of two angled struts 418.

The two upper rows of angled struts includes a total of three axialwindow frame members 430 and a total of three axially extending struts432 located equidistant between the window frame members 430 with threeangled struts 418 and three angled struts 422 extending between a windowframe member 430 and an adjacent axially extending strut 432. The frame402 can also include three additional rows of angled struts located atthe inflow end of the frame (not shown in FIG. 10), similar toembodiments discussed above. The lower end of each window frame member430 can be connected to the upper ends of two angled struts of anadjacent row (the third row from the outflow end of the frame) at alocation 444. Thus, in this embodiment, the lower end of each axiallyextending strut 432 is not connected to any struts of the adjacent row.

FIG. 11 shows a portion of a frame 502, according to another embodiment.In FIG. 11, only one-third of the circumference two upper rows of angledstruts (the rows closest to the outflow end) are shown. The frame 502can have axial window frame members 530 extending between locations 542defined by the convergence of the lower ends of two angled struts 552and locations 554 defined by the convergence of the upper ends of twoangled struts 518. The frame 502 can have axially extending struts 532extending between locations 546 defined by the convergence of the upperends of two angled struts 522 and locations 548 defined by theconvergence of the lower ends of two angled struts 518. The axiallyextending struts 532 in this embodiment can be longer than the windowframe members 530 to account for the greater distance between locations546, 548 compared to the distance between locations 542, 544.

The two upper rows of angled struts includes a total of three axialwindow frame members 530 and a total of three axially extending struts532 located equidistant between the window frame members 530 with threeangled struts 518 and three angled struts 522 extending between a windowframe member 530 and an adjacent axially extending strut 532. The frame502 can also include three additional rows of angled struts located atthe inflow end of the frame (not shown in FIG. 11), similar toembodiments discussed above. The lower end of each axially extendingstrut 532 can be connected to the upper ends of two angled struts of anadjacent row (the third row from the outflow end of the frame) at alocation 548. Thus, in this embodiment, the lower end of each windowframe member 530 is not connected to any angled struts of the adjacentrow.

FIG. 12 shows a portion of a frame 602, according to another embodiment.In FIG. 12, only one-third of the circumference of the two upper rows ofangled struts (the rows closest to the outflow end) is shown. The frame602 can have axial window frame members 630 extending between locations642 defined by the convergence of the upper ends of two angled struts622 and locations 644 defined by the convergence of the upper ends oftwo angled struts 618. The frame 602 can have axially extending struts632 extending between locations 646 defined by the convergence of thelower ends of two angled struts 622 and locations 648 defined by theconvergence of the lower ends of two angled struts 618.

In the embodiment of FIG. 12, there are two such axially extendingstruts 632 spaced between each pair of window frame members 630. Inparticular, for each pair of window frame members, there are threeangles struts 618 and three angles struts 622 between each window framemember 630 and the closest axially extending strut 632, and two anglesstruts 618 and two angles struts 622 between the two axially extendingstruts 632. Thus, for the entire frame 602, the two upper rows of angledstruts includes a total of three axial window frame members 630 and atotal of six axially extending struts 632.

The frame 602 can also include three additional rows of angled strutslocated at the inflow end of the frame (not shown in FIG. 12), similarto embodiments discussed above. The lower end of each axially extendingstrut 632 can be connected to the upper ends of two angled struts of anadjacent row (the third row from the outflow end of the frame) at alocation 648. Thus, in this embodiment, the lower end of each windowframe member 630 is not connected to any struts of the adjacent row.

FIG. 13 shows a portion of a frame 702, according to another embodiment.In FIG. 13, only one-third of the circumference of the two upper rows ofangled struts (the rows closest to the outflow end) is shown. The frame702 can have axial window frame members 730 extending between locations742 defined by the convergence of the lower ends of two angled struts722 and locations 744 defined by the convergence of the upper ends oftwo angled struts 718. The frame 702 can have axially extending struts732 extending between locations 746 defined by the convergence of theupper ends of two angled struts 722 and locations 748 defined by theconvergence of the lower ends of two angled struts 718.

In the embodiment of FIG. 13, there are two such axially extendingstruts 732 spaced between each pair of window frame members 730. Inparticular, for each pair of window frame members, there are threeangles struts 718 and three angles struts 722 between each window framemember 730 and the closest axially extending strut 732, and two anglesstruts 718 and two angles struts 722 between the two axially extendingstruts 732. Thus, for the entire frame 702, the two upper rows of angledstruts includes a total of three axial window frame members 730 and atotal of six axially extending struts 732. Also, struts 732 can belonger than window frame members 730 to account for the greater distancebetween locations 746, 748 compared to the distance between locations742, 744.

The frame 702 can also include three additional rows of angled strutslocated at the inflow end of the frame (not shown in FIG. 13), similarto embodiments discussed above. The lower end of each axially extendingstrut 732 can be connected to the upper ends of two angled struts of anadjacent row (the third row from the outflow end of the frame) at alocation 748. Thus, in this embodiment, the lower end of each windowframe member 730 is not connected to any struts of the adjacent row.

The prosthetic valve embodiments disclosed herein can be surgicallyimplanted and/or can be delivered using a delivery apparatus, such as acatheter. The prosthetic valve can be mounted in a crimped state on oradjacent an inflatable balloon or equivalent expansion mechanism of thedelivery apparatus. The delivery apparatus and crimped prosthetic valvecan be inserted into the patient's vasculature and advanced through thepatient's body using known techniques.

In one implementation, the prosthetic valve is delivered in atransfemoral procedure in which the delivery apparatus is inserted intoa femoral artery and advanced through the aorta to the native aorticvalve (or another native valve of the heart). In another implementation,the prosthetic valve can be delivered in a transventricular procedure inwhich the delivery apparatus is inserted through a small surgicalopening in the chest and another surgical opening in the wall of theheart, such as the wall of the left ventricle. In anotherimplementation, the prosthetic valve can be delivered in a transaorticprocedure in which the delivery apparatus is inserted through a smallsurgical opening in the chest and another surgical opening in theascending aorta, at a location above the aortic valve. In anotherimplementation, the prosthetic valve is a replacement venous valve forimplantation in a vein, or a replacement for another valve with a lowerflow rate relative to the aortic valve.

When the prosthetic valve is positioned at the desired deploymentlocation (e.g., within the native aortic valve), the balloon of thedelivery apparatus can be inflated to radially expand the prostheticvalve. In some embodiments, upon full expansion of the prosthetic valve,the outer skirt of the prosthetic valve can be forced into contact withthe surrounding tissue of the native valve, establishing a seal betweenthe outer surface of the frame and the surrounding tissue. The frame ofthe prosthetic valve, when in the radially compressed, mountedconfiguration, can comprise an inflow end portion that has an outerdiameter that is smaller than the outer diameter of the outflow endportion of the frame.

When constructed of a self-expanding material, the prosthetic valve canbe crimped to a radially compressed state and restrained in thecompressed state by insertion into a sheath or equivalent mechanism of adelivery catheter. After the delivery apparatus is inserted into thebody and advanced to position the prosthetic valve at the desireddeployment location, the prosthetic valve can be advanced from thedelivery sheath. As the prosthetic valve is deployed from the deliverysheath, the prosthetic valve can radially self-expand to its functionalsize.

The prosthetic heart valve can comprise commissure portions of theleaflets extending radially outwardly through corresponding window frameportions to locations outside of the frame and sutured to the sidestruts of the commissure window frame. To minimize the crimp profile ofthe prosthetic valve, the window frame portions can be depressedradially inwardly relative to the surrounding portions of the frame,such as the frame portions extending between adjacent commissurewindows, when the prosthetic valve is radially compressed to thecollapsed configuration on a catheter.

For example, the commissure windows of the frame can be depressedinwardly a radial distance, such as between 0.2 mm and 1.0 mm, relativeto the portions of the frame extending between adjacent commissurewindows when the prosthetic valve is radially collapsed. In this way,the outer diameter of the outflow end portion the prosthetic valvecomprising the commissure portions can be generally consistent, asopposed to the commissure portions jutting outward from the surroundingportions of the prosthetic valve, which could hinder delivery of theprosthetic valve into the body. Even with the radially depressedcommissure window frames, the outer diameter of the inflow end portionof the frame can still be smaller than, or about equal to, the outerdiameter of the outflow end portion of the frame when the prostheticvalve is radially collapsed on the catheter, allowing for a minimal orreduced maximum overall diameter of the prosthetic valve. By minimizingor reducing the diameter of the prosthetic valve when mounted on thedelivery catheter, the diameter of a delivery catheter through which theprosthetic valve is advanced can also be minimized or reduced. Thisallows the prosthetic valve to be delivered through smaller vessels inthe body, making the delivery procedure less invasive, in general.

Additional details relevant to delivery of the prosthetic heart valvesdisclosed herein are provided in U.S. Patent Publication 2011/0123529,which is incorporated herein by reference.

General Considerations

For purposes of this description, certain aspects, advantages, and novelfeatures of the embodiments of this disclosure are described herein. Thedisclosed methods, apparatuses, and systems should not be construed aslimiting in any way. Instead, the present disclosure is directed towardall novel and nonobvious features and aspects of the various disclosedembodiments, alone and in various combinations and sub-combinations withone another. The methods, apparatuses, and systems are not limited toany specific aspect or feature or combination thereof, nor do thedisclosed embodiments require that any one or more specific advantagesbe present or problems be solved.

Although the operations of some of the disclosed methods are describedin a particular, sequential order for convenient presentation, it shouldbe understood that this manner of description encompasses rearrangement,unless a particular ordering is required by specific language. Forexample, operations described sequentially may in some cases berearranged or performed concurrently. Moreover, for the sake ofsimplicity, the attached drawings may not show the various ways in whichthe disclosed methods can be used in conjunction with other methods. Asused herein, the terms “a”, “an”, and “at least one” encompass one ormore of the specified element. That is, if two of a particular elementare present, one of these elements is also present and thus “an” elementis present. The terms “a plurality of” and “plural” mean two or more ofthe specified element.

As used herein, the term “and/or” used between the last two of a list ofelements means any one or more of the listed elements. For example, thephrase “A, B, and/or C” means “A”, “B”, “C”, “A and B”, “A and C”, “Band C”, or “A, B, and C”.

In view of the many possible embodiments to which the principles of thedisclosed invention may be applied, it should be recognized that theillustrated embodiments are only preferred examples of the invention andshould not be taken as limiting the scope of the invention. Rather, thescope of the invention is defined by the following claims. I thereforeclaim as my invention all that comes within the scope and spirit ofthese claims.

I claim:
 1. A prosthetic device for implantation at a cardiac valveannulus, the prosthetic device comprising: an annular frame having aninflow end, an outflow end, at least four circumferentially extendingrows of angled struts, and a plurality of axial frame members bridgingtwo of the circumferentially extending rows of angled struts that areclosest to the outflow end, wherein each axial frame member has a firstend closer to the inflow end and a second end closer to the outflow end,and the plurality of axial frame members comprises a plurality ofaxially extending leaflet attachment members and a plurality of axialstruts in a 1:1 ratio, and further wherein there is exactly one row ofangled struts linking the second ends of the axial frame members and nomore than one row of angled struts between the second ends of theplurality of axial frame members and the outflow end, and there are atleast three rows of angled struts between the first ends of theplurality of axial frame members and the inflow end.
 2. The device ofclaim 1, further comprising a leaflet structure positioned within theframe having a plurality of commissures that are secured to the frame atthe leaflet attachment members, wherein the commissures are secured tothe leaflet attachment members adjacent to the outflow end of the frame.3. The device of claim 2, wherein the leaflet structure comprisesexactly three leaflets arranged in a tricuspid configuration, whereinthe frame comprises exactly three axial struts and exactly three leafletattachment members, and wherein exactly three angled struts separateadjacent axial frame members along each of the two rows of angledstruts.
 4. The device of claim 1, wherein at least three angled strutsseparate adjacent axial frame members along each of the two rows ofangled struts that are closest to the outflow end.
 5. The device ofclaim 1, wherein exactly six angled struts separate adjacent leafletattachment members along each of the two rows that are closest to theoutflow end and exactly three angled struts separate adjacent axialframe members along each of the two rows that are closest to the outflowend, such that each axial strut is halfway between adjacent leafletattachment members.
 6. The device of claim 1, wherein each axial framemember extends between locations defined by a convergence of adjacentangled struts.
 7. The device of claim 1, further comprising an innerskirt secured to an interior portion of the annular frame, and an outerskirt secured to an exterior portion of the annular frame.
 8. The deviceof claim 1, wherein the frame comprises exactly four rows of angledstruts.
 9. An annular frame for a prosthetic heart valve, the annularframe comprising: an inflow end, an outflow end, at least fourcircumferentially extending rows of angled struts, and a plurality ofaxial frame members spaced angularly around the circumference of theframe, wherein the plurality of axial frame members bridge two of thecircumferentially extending rows of angled struts that are closest tothe outflow end, and wherein each of the two rows comprise at leastthree angled struts between adjacent axial frame members, and furtherwherein each axial frame member has a first end closer to the inflow endand a second end closer to the outflow end, and there is exactly one rowof angled struts linking the second ends of the axial frame members andno more than one row of angled struts between the second ends of theplurality of axial frame members and the outflow end, and there are atleast three rows of angled struts between the first ends of theplurality of axial frame members and the inflow end.
 10. The frame ofclaim 9, and wherein each of the two rows that are closest to theoutflow end comprises exactly three angled struts between adjacent axialframe members.
 11. The frame of claim 10, wherein the plurality of axialframe members comprises a plurality of axially extending leafletattachment members, and wherein each of the two rows that are closest tothe outflow end comprise exactly six angled struts between adjacentleaflet attachment members.
 12. The frame of claim 11, wherein theleaflet attachment members extend between locations defined by aconvergence of upper ends of adjacent angled struts, and the axialstruts extend between locations defined by a convergence of lower endsof adjacent angled struts.
 13. The frame of claim 9, wherein theplurality of axial frame members comprises a plurality of axiallyextending leaflet attachment members and a plurality of axial struts,and wherein each of the two rows that are closest to the outflow endcomprises four angled struts between adjacent axial struts and eightangled struts between adjacent leaflet attachment members.
 14. The frameof claim 9, wherein the plurality of axial frame members comprises aplurality of leaflet attachment members and a plurality of axial strutsin a 1:1 ratio.
 15. The frame of claim 14, wherein the plurality ofaxial frame members comprises exactly three leaflet attachment membersand exactly three axial struts.
 16. The frame of claim 9, wherein: theplurality of axial frame members comprises a plurality of axiallyextending leaflet attachment members and a plurality of axial struts;the two rows of angled struts that are closest to the outflow endcomprise a first row and a second row, wherein the first row is closerto the outflow end than the second row; the leaflet attachment membersextend from locations defined by the convergence of the upper ends ofadjacent angled struts along the first row to locations defined by theconvergence of the lower ends of adjacent angled struts along the secondrow; and the axial struts extend between locations defined by theconvergence of the lower ends of adjacent angled struts along the firstrow to locations defined by the convergence of upper ends of adjacentangled struts along the second row.
 17. The frame of claim 9, whereinthe frame comprises exactly four rows of angled struts.
 18. A prostheticdevice for implantation at a cardiac valve annulus, the prostheticdevice comprising: an annular frame having an inflow end, an outflowend, at least four rows of circumferentially extending angled struts,and exactly six axial frame members bridging two rows of the four rowsof circumferentially extending angled struts, wherein the plurality ofaxial frame members comprises exactly three axially extending leafletattachment members and exactly three axial struts; wherein each axialframe member has a first end closer to the inflow end and a second endcloser to the outflow end, and there is exactly one row of angled strutslinking the second ends of the six axial frame members and no more thanone row of angled struts between the second ends of the six axial framemembers and the outflow end, and there are at least three rows of angledstruts between the first ends of the six axial frame members and theinflow end; wherein each of the two rows bridged by the six axial framemembers comprises exactly three angled struts between each pair of aleaflet attachment member and an adjacent axial strut and exactly sixangled struts between adjacent leaflet attachment members; and atri-leaflet valve member positioned within the frame having commissuresthat are secured to the frame at the leaflet attachment members; whereinthe commissures are secured to the leaflet attachment members adjacentto the outflow end of the frame.
 19. The prosthetic device of claim 18,wherein: the at least four rows comprise a first row and a second row,wherein the first row is closer to the outflow end than the second row,the leaflet attachment members extend from locations defined by aconvergence of upper ends of adjacent angled struts along the first rowto locations defined by a convergence of upper ends of adjacent angledstruts along the second row, and the axial struts extend betweenlocations defined by a convergence of lower ends of adjacent angledstruts along the first row to locations defined by a convergence oflower ends of adjacent angled struts along the second row.
 20. Theprosthetic device of claim 18, wherein the frame comprises exactly fourrows of circumferentially extending angled struts.